Package org.mapstruct.ap.spi

Interface MappingExclusionProvider

  • @Experimental("This SPI can have its signature changed in subsequent releases")
public interface MappingExclusionProvider
    A service provider interface that is used to control if MapStruct is allowed to generate automatic sub-mapping for a given TypeElement.

    When generating the implementation of a mapping method, MapStruct will apply the following routine for each attribute pair in the source and target object:

    • If source and target attribute have the same type, the value will be simply copied from source to target. If the attribute is a collection (e.g. a `List`) a copy of the collection will be set into the target attribute.
    • If source and target attribute type differ, check whether there is a another mapping method which has the type of the source attribute as parameter type and the type of the target attribute as return type. If such a method exists it will be invoked in the generated mapping implementation.
    • If no such method exists MapStruct will look whether a built-in conversion for the source and target type of the attribute exists. If this is the case, the generated mapping code will apply this conversion.
    • If no such method was found MapStruct will try to generate an automatic sub-mapping method that will do the mapping between the source and target attributes
    • If MapStruct could not create a name based mapping method an error will be raised at build time, indicating the non-mappable attribute and its path.

    With this SPI the last step before raising an error can be controlled. i.e. A user can control whether MapStruct is allowed to generate such automatic sub-mapping method (for the source or target type) or not.

    Since:
    1.2
    Author:
    Filip Hrisafov

    • Method Detail

      • isExcluded

        boolean isExcluded​(TypeElement typeElement)
        Checks if MapStruct should not generate an automatic sub-mapping for the provided TypeElement, i.e. MapStruct will not try to descent into this class and won't try to automatically map it with some other type. The given typeElement will be excluded from the automatic sub-mapping generation
        Parameters:
        typeElement - that needs to be checked
        Returns:
        true if MapStruct should exclude the provided TypeElement from an automatic sub-mapping